Package com.mckoi.database

Class IndexSetStore.MappedListBlock

java.lang.Object

com.mckoi.util.IntegerListBlockInterface

com.mckoi.util.BlockIntegerList.IntArrayListBlock

com.mckoi.database.IndexSetStore.MappedListBlock

Enclosing class:

IndexSetStore

private final class IndexSetStore.MappedListBlock
extends BlockIntegerList.IntArrayListBlock

An IntegerListBlockInterface implementation that maps a block of a list to an underlying file system representation.

Field Summary

Fields

Modifier and Type	Field	Description
private long	block_p	A pointer to the area where this block can be found.
private byte	compact_type	How this block is compacted in the store.
private long	first_entry	The first entry in the block.
private long	last_entry	The last entry in the block.
private java.lang.Object	lock	Lock object.
private int	max_block_size	The maximum size of the block.
private boolean	mutable_block	Set to true if the loaded block is mutable.

Fields inherited from class com.mckoi.util.BlockIntegerList.IntArrayListBlock

array, count

Fields inherited from class com.mckoi.util.IntegerListBlockInterface

next, previous

Constructor Summary

Constructors

Constructor	Description
MappedListBlock(int block_size_in)	Creates an empty block.
MappedListBlock(long first_e, long last_e, long mapped_p, int size, byte compact_type, int max_block_size)	Constructor.

Method Summary

Modifier and Type	Method	Description
int	bottomInt()	Overwritten from IntArrayListBlock, returns the first entry of the block.
long	copyTo(Store dest_store)	Copies the index data in this block to a new block in the given store and returns a pointer to the new block.
int[]	getArray(boolean immutable)	Overwritten from IntArrayListBlock, this returns the int[] array that contains the contents of the block.
int	getArrayLength()	Overwritten from IntArrayListBlock, returns the capacity of the block.
long	getBlockPointer()	Returns a pointer to the area that contains this block.
byte	getCompactType()	Returns the compact type of this block.
private void	prepareMutate(boolean immutable)	Makes the block mutable if it is immutable.
int	topInt()	Overwritten from IntArrayListBlock, returns the last entry of the block.
long	writeToStore()	Writes this block to a new sector in the index file and updates the information in this object accordingly.

Methods inherited from class com.mckoi.util.BlockIntegerList.IntArrayListBlock

addInt, binarySearch, canContain, clear, copyTo, copyTo, insertIntAt, intAt, isEmpty, isFull, iterativeSearch, iterativeSearch, moveTo, removeIntAt, searchFirst, searchFirst, searchLast, searchLast, setIntAt, size, toString

Methods inherited from class com.mckoi.util.IntegerListBlockInterface

hasChanged

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

first_entry

private long first_entry

The first entry in the block.

last_entry

private long last_entry

The last entry in the block.

block_p

private long block_p

A pointer to the area where this block can be found.

lock

private java.lang.Object lock

Lock object.

mutable_block

private boolean mutable_block

Set to true if the loaded block is mutable.

compact_type

private byte compact_type

How this block is compacted in the store. If this is 1 the elements are stored as shorts, if it is 2 - ints, and if it is 3 - longs.

max_block_size

private final int max_block_size

The maximum size of the block.

Constructor Detail

MappedListBlock

public MappedListBlock(long first_e,
                       long last_e,
                       long mapped_p,
                       int size,
                       byte compact_type,
                       int max_block_size)

Constructor.

MappedListBlock

public MappedListBlock(int block_size_in)

Creates an empty block.

Method Detail

getBlockPointer

public long getBlockPointer()

Returns a pointer to the area that contains this block.

getCompactType

public byte getCompactType()

Returns the compact type of this block.

copyTo

public long copyTo(Store dest_store)
            throws java.io.IOException

Copies the index data in this block to a new block in the given store and returns a pointer to the new block.

Throws:

java.io.IOException

writeToStore

public long writeToStore()
                  throws java.io.IOException

Writes this block to a new sector in the index file and updates the information in this object accordingly.

Returns the sector the block was written to.

Throws:

java.io.IOException

getArray

public int[] getArray(boolean immutable)

Overwritten from IntArrayListBlock, this returns the int[] array that contains the contents of the block. In this implementation, we determine if the array has been read from the index file. If it hasn't we read it in, otherwise we use the version in memory.

Overrides:

getArray in class BlockIntegerList.IntArrayListBlock

getArrayLength

public int getArrayLength()

Overwritten from IntArrayListBlock, returns the capacity of the block.

Overrides:

getArrayLength in class BlockIntegerList.IntArrayListBlock

prepareMutate

private void prepareMutate(boolean immutable)

Makes the block mutable if it is immutable. We must be synchronized on 'lock' before this method is called.

topInt

public int topInt()

Overwritten from IntArrayListBlock, returns the last entry of the block.

Overrides:

topInt in class BlockIntegerList.IntArrayListBlock

bottomInt

public int bottomInt()

Overwritten from IntArrayListBlock, returns the first entry of the block.

Overrides:

bottomInt in class BlockIntegerList.IntArrayListBlock